Facebook is threatening to take legal action against the creators of an online "dating" site that features 250,000 profiles of men and women whose photos and personal details were scraped off the social networking giant's site and used without their permission.

The site, called Lovely Faces, was ostensibly set up as part of an attempt to demonstrate to the world how easy it is to misuse data that is publicly posted on sites such as Facebook. It allows users to search for men and women using their real names, or by categories such as "easy going", "sly" and "smug."

The site was available briefly earlier today, but was unavailable this afternoon. However, one sample of the kind of profiles being served up on the site can be seen here .

Paolo Cirio, an Italian media artist, and Alessandro Ludovico, a media critic and editor in chief of Neural magazine in Italy, are the site's creators. On a site explaining their caper , the two admit to using an automated bot program to systematically scrape publicly available information from 1 million Facebook profiles (PDF document) , over a period of several months.

The scraped data was downloaded into a database and run against a face recognition software program that grouped the profiles into six pre-defined categories based on their facial expressions. People were grouped under topics based one their expressions, such as "climber", "easy going", "funny", "mild", "sly" and "smug". The software matched a total of 250,000 people to at least one of these categories.

"The categories are among the most popular that we usually use to define a person at a distance, without knowing him/her, or judging based only on a few behaviors," Cirio and Ludovico claimed on their site. "The resulting scenario is that different elements forming the identities can be remixed, re-contextualized and re-used at will."

The goal of the experiment apparently is to highlight the often underestimated consequences of publicly posting personal data on social media sites such as Facebook .

"The price users pay is being categorized as what they really are, or better, how they choose to be represented in the most famous and crowded online environment," the duo noted. "The project starts to dismantle the trust that 500 million people have put in Facebook."

They say Lovely Faces highlights how an "endlessly cool place" such as Facebook is also a goldmine for identity theft. "But that's the very nature of Facebook and social media in general. If we start to play with the concepts of identity theft and dating, we should be able to unveil how fragile a virtual identity given to a proprietary platform can be."

Facebook spokesman Barry Schnitt said in an e-mailed statement that scraping people's information from its site is a violation of its terms.

"We have taken, and will continue to take, aggressive legal action against organizations that violate these terms," Schnitt noted. "We've already been in touch with Lovely-Faces to demand that they delete the data and we will take additional action as necessary."